This study is intended to support and expand a program of monitoring numbers and immunologic reactivity of lymphocytes in patients with neoplasms presenting for radiation therapy. It is generally agreed that immune responses, indicated by measurement of tritiated thymidine incorporation into newly synthesized DNA in cultures of stimulated lymphocytes, may play an important role in control of malignancies. To better understand the role of lymphocytes in immunological competence and the effects of radiotherapy on immunity, patients with neoplasms at different anatomical sites including lung, breast, uterus, head and neck and gastrointestinal tract are tested to determine whether degree of disease progression, site of neoplasm, prior treatment with surgery or chemotherapy, or different radiation-treatment modalities influence the suppressive effects of radiation on numbers and responses of lymphocyte. Other objectives include whether depressed immune responses of patients recover completely or partially after treatment, whether recovery can be correlated with prognosis, and whether recovery is related to clinical stage, site of lesion, prior treatments, or volume of tissue exposed to radiation during treatment. Blood samples from patients before, during, at the end of radiotherapy, and for months to years after treatment will be tested for in vitro responses to mitogens phytohemagglutinin, concanavalin A, and pokeweed mitogen and to the antigens tuberculin purified protein derivative, streptokinase/streptodoinase, tricophyton mix, and monilia albicans. This study should provide information relative to factors that influence immune response in patients treated with radiotherapy and the correlation, if any, of responses and recurrent or metastatic disease.